The authors of this article compare American and Korean reactions to the persuasiveness of environmental advertising campaigns that include pledges. Findings indicate that environmental advertising effectiveness depends on how much effort recipients put into making environmental pledges prior to viewing the advertisements. Study 1 demonstrates that when environmental pledges requesting more effort precede ad messages, Americans are more persuaded but Koreans are less persuaded. Study 2 extends the findings and rules out an alternative explanation—mere-effort effect—by showing that the results are replicated only with an issue-relevant pledge, but not with an issue-irrelevant pledge.